To disable automatic updates on Macs:

• Open System Preferences… under the apple menu
• Click on the App Store
• Uncheck the Automatically check for updates box

To disable automatic updates on iPhone/iPad:

• Open Settings
• Tap on iTunes & App Store
• Under the AUTOMATIC DOWNLOADS section turn off all available options

Android gives you a fair amount of freedom about updates. You can turn off all updates, or limit updates to Wi-Fi downloads only. You can also enable updates for only specific apps - so for example, you might want the latest versions of apps you use very frequently, but you don't want to waste bandwidth downloading updates for other apps that will be launched only once every three months.

To turn updates on or off, follow these steps:

• Open Google Play.
• Tap the hamburger icon (three horizontal lines) on the top-left.
• Tap Settings.
• Tap Auto-update apps.
• To disable automatic app updates, select Do not auto-update apps.

If you want to instead auto-update apps only when you're connected to a WiFi? network, tap Auto-update apps over Wi-Fi only in the same pop-up. Android also lets you choose which apps you want to update automatically. To turn on auto-update for any app, go to the app page in the Google Play app. Tap the three vertical dots in the top right. Check Auto-update.

To disable automatic updates on Ubuntu Unity:

• Open the Unity Dash.
• Search for 'Software & Updates'
• Select the 'Updates' tab.
• Change 'Automatically check for updates' from 'Daily' to 'Never'

To disable automatic updates on command line:

Using your favorite editor open the file /etc/apt/apt.conf.d/10periodic and change the 1 to 0:

APT::Periodic::Update-Package-Lists "1"
APT::Periodic::Update-Package-Lists "0";

Article on how to disable updates